Question: What fan convention starts with the letter "v"?
Paraphrase: What fan tradition begins with the letter "v"?
SPARQL (Wikidata): SELECT DISTINCT ?sbj ?sbj_label WHERE { ?sbj wdt:P31 wd:Q1129398 . ?sbj rdfs:label ?sbj_label . FILTER(STRSTARTS(lcase(?sbj_label), 'v')) . FILTER (lang(?sbj_label) = 'en') } LIMIT 25 
Answer: VidCon, VidCon